U.S. patent number 8,744,342 [Application Number 12/996,956] was granted by the patent office on 2014-06-03 for method and a device for identifying at least one terminal for which signals transferred between the at least one terminal and a base station have to be relayed by a relay.
This patent grant is currently assigned to Mitsubishi Electric Corporation. The grantee listed for this patent is Herve Bonneville, Loic Brunel, Damien Castelain, Nicolas Gresset. Invention is credited to Herve Bonneville, Loic Brunel, Damien Castelain, Nicolas Gresset.
United States Patent |
8,744,342 |
Brunel , et al. |
June 3, 2014 |
Method and a device for identifying at least one terminal for which
signals transferred between the at least one terminal and a base
station have to be relayed by a relay
Abstract
A method for identifying at least one terminal for which signals
transferred between the at least one terminal and a base station of
a wireless cellular telecommunication network have to be relayed by
a relay, the base station providing a random access channel
enabling a terminal to notify to the base station the presence of
the terminal by transferring a random access signal to the base
station. The relay device transfers the random access signal to the
base station, receives the list, identifies, from the received
list, at least one terminal for which signals transferred between
the at least one identified terminal and the base station have to
be relayed by the relay, and relays signals between the at least
one identified terminal and the base station.
Inventors: |
Brunel; Loic (Rennes Cedex,
FR), Castelain; Damien (Rennes Cedex, FR),
Gresset; Nicolas (Rennes Cedex, FR), Bonneville;
Herve (Rennes Cedex, FR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Brunel; Loic
Castelain; Damien
Gresset; Nicolas
Bonneville; Herve |
Rennes Cedex
Rennes Cedex
Rennes Cedex
Rennes Cedex |
N/A
N/A
N/A
N/A |
FR
FR
FR
FR |
|
|
Assignee: |
Mitsubishi Electric Corporation
(Tokyo, JP)
|
Family
ID: |
40039996 |
Appl.
No.: |
12/996,956 |
Filed: |
June 9, 2009 |
PCT
Filed: |
June 09, 2009 |
PCT No.: |
PCT/EP2009/057123 |
371(c)(1),(2),(4) Date: |
March 01, 2011 |
PCT
Pub. No.: |
WO2009/150160 |
PCT
Pub. Date: |
December 17, 2009 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20110306334 A1 |
Dec 15, 2011 |
|
Foreign Application Priority Data
|
|
|
|
|
Jun 11, 2008 [EP] |
|
|
08158040 |
|
Current U.S.
Class: |
455/9; 455/557;
370/492; 455/24; 370/315 |
Current CPC
Class: |
H04W
88/04 (20130101); H04W 74/08 (20130101) |
Current International
Class: |
H04B
1/60 (20060101) |
Field of
Search: |
;370/225-228,315,329-333
;455/7-13.1,450-455 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
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1 898 562 |
|
Mar 2008 |
|
EP |
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WO 2006104105 |
|
Jun 2006 |
|
WO |
|
Other References
Esseling, N. et al., "A Forwarding Concept for HiperLAN/2",
Elsevier Computer Networks, vol. 37, pp. 25-32 (Sep. 1, 2001).
cited by applicant .
International Search Report Issued Sep. 10, 2009 in PCT/EP09/057123
filed Jun. 9, 2009. cited by applicant .
U.S. Appl. No. 12/997,367, filed Dec. 10, 2010, Brunel, et al.
cited by applicant.
|
Primary Examiner: Perez-Gutierrez; Rafael
Assistant Examiner: Fang; Keith
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier
& Neustadt, L.L.P.
Claims
The invention claimed is:
1. A method, implemented on a communication system, for identifying
at least one terminal for which signals transferred between the at
least one terminal and a base station of a wireless cellular
telecommunication network have to be relayed by a relay device, the
base station providing a random access channel enabling a terminal
to notify to the base station the presence of the terminal by
transferring a random access signal to the base station, the method
comprising: transferring, by the relay device, a random access
signal to the base station over the random access channel to notify
the base station of the presence of the relay device, wherein the
relay device is initially considered by the base station to be a
new terminal in an area managed by the base station after receiving
the random access signal; informing, by the relay device, the base
station, after a response to the transferred random access signal
is received, that the relay device is a relay that is configured to
relay signals between the base station and at least one terminal,
for authentication as the relay that is configured to relay signals
between the base station and at least one terminal by a core
network device; relaying, by the relay device, signals between at
least one terminal and the base station.
2. The method according to claim 1, further comprising: receiving a
message requesting the relay device to switch in an idle mode; and
interrupting the relay of the signals transferred between each
identified terminal and the base station.
3. The method according to claim 2, further comprising, executed
prior to the receiving the message, transferring information
representative of measurement of signals transferred by at least
one terminal to the base station which handles the terminal.
4. The method according to claim 3, wherein information
representative of measurement of signals transferred by at least
one terminal are information identifying the resource blocks of at
least one channel between the base station and the terminal for
which the relay device measures the highest receive signals power
strength.
5. The method according to the claim 4, wherein a management entity
manages the relay device located in the area managed by the base
station.
6. The method according to the claim 5, further comprising:
receiving a list; identifying, from the received list, at least one
terminal for which signals transferred between the at least one
identified terminal and the base station have to be relayed by the
relay device, wherein the management entity receives the
information identifying the resource blocks, and the method further
comprising, executed by the management entity: obtaining, from the
base station, at least one identifier of the terminal to which the
identified resource blocks are allocated; and determining, from the
at least one obtained identifier of terminal, the list of at least
one terminal.
7. The method according to claim 6, further comprising, executed by
the management entity, obtaining, from the base station, at least
one identifier of the terminal for which the transmission quality
between the terminal and the base station is below a given
threshold, and the list of at least one terminal is further
determined from the at least one obtained identifier of terminal
for which the transmission quality between the terminal and the
base station is below the given threshold.
8. The method according to claim 6, wherein the message and/or the
information transferred between the management entity and the relay
device are transferred via a radio interface of the base
station.
9. The method according to claim 5, further comprising: receiving a
list; identifying, from the received list, at least one terminal
for which signals transferred between the at least one identified
terminal and the base station have to be relayed by the relay
device, the method further comprising, executed by the management
entity, receiving information representative of measurement of
signals transferred between the base station and the relay device,
and the list of at least one terminal is further determined from
information representative of measurement of signals transferred
between the base station and the relay device.
10. The method according to claim 5, further comprising, executed
by the management entity, transferring a message requesting the
relay device to stop to transfer signals transferred between the at
least one terminal and the base station which handles the terminal
if signals do not need to be relayed.
11. The method according to claim 10, further comprising, executed
by the management entity, transferring a paging message to the
relay device.
12. The method according to claim 1, wherein the base station
allocates an identifier to the relay device, the identifier being
selected among identifiers to be allocated to terminals.
13. The method according to claim 1, further comprising: receiving
a list; identifying, from the received list, at least one terminal
for which signals transferred between the at least one identified
terminal and the base station have to be relayed by the relay
device, wherein the at least one identified terminal is a terminal
identified in the received list.
14. The method according to claim 1, wherein the relay device
identifies at least one terminal for which signals transferred
between the at least one terminal and the base station have to be
relayed by the relay device.
15. The method according to claim 14, wherein the relay device
receives at least one identifier of a terminal, the identified
terminal being identified from the at least one received
identifier.
16. A relay device of a wireless cellular telecommunication network
in which the relay device is configured to relay signals
transferred between at least one terminal and a base station, and
the base station provides a random access channel enabling a
terminal to notify to the base station the presence of the terminal
by transferring a random access signal to the base station, the
relay device comprising: means for transferring a random access
signal to the base station over the random access channel to notify
the base station of the presence of the relay device, wherein the
relay device is initially considered by the base station to be a
new terminal in an area managed by the base station after receiving
the random access signal; means for informing the base station,
after a response to the transferred random access signal is
received, that the relay device is a relay that is configured to
relay signals between the base station and at least one terminal,
for authentication as the relay that is configured to relay signals
between the base station and at least one terminal by a core
network device; and means for relaying signals between at least one
terminal and the base station.
17. A non-transitory computer readable medium including computer
executable instructions or portions of code for causing a relay
device of a wireless cellular telecommunication network, in which
the relay device is configured to relay signals transferred between
at least one terminal and a base station and the base station
provides a random access channel enabling a terminal to notify to
the base station the presence of the terminal by transferring a
random access signal to the base station, to perform a method
comprising: transferring, by the relay device, a random access
signal to the base station over the random access channel to notify
the base station of the presence of the relay device, wherein the
relay device is initially considered by the base station to be a
new terminal in an area managed by the base station after receiving
the random access signal; informing, by the relay device, the base
station, after a response to the transferred random access signal
is received, that the relay device is a relay that is configured to
relay signals between the base station and at least one terminal,
for authentication as the relay that is configured to relay signals
between the base station and at least one terminal by a core
network device; and relaying, by the relay device, signals between
at least one terminal and the base station.
18. A method, implemented on a communication system, for notifying
the presence of a relay device to a base station, the relay device
being able to relay signals transferred between at least one
terminal and the base station of a wireless cellular
telecommunication network, the base station providing a random
access channel enabling a terminal to notify to the base station
the presence of the terminal by transferring a random access signal
to the base station, the method comprising: transferring, by the
relay device, a random access signal to the base station over the
random access channel to notify the base station of the presence of
the relay device, wherein the relay device is initially considered
by the base station to be a new terminal in an area managed by the
base station after receiving the random access signal; and
informing, by the relay device, the base station, after a response
to the transferred random access signal is received, that the relay
device is a relay that is configured to relay signals between the
base station and at least one terminal, for authentication as the
relay that is configured to relay signals between the base station
and at least one terminal by a core network device.
19. A method, implemented on a communication system, for notifying
the presence of a relay device to a base station, the relay device
being able to relay signals transferred between at least one
terminal and the base station of a wireless cellular
telecommunication network, the base station providing a random
access channel enabling a terminal to notify to the base station
the presence of the terminal by transferring a random access signal
to the base station, the method comprising: receiving, by the base
station, a random access signal from the relay device over the
random access channel to notify the base station of the presence of
the relay device, wherein the relay device is initially considered
by the base station to be a new terminal in an area managed by the
base station after receiving the random access signal; and
receiving, by the base station, after a response to the transferred
random access signal is transferred, information from the relay
device notifying that the relay device is a relay that is
configured to relay signals between the base station and at least
one terminal, for authentication as the relay that is configured to
relay signals between the base station and at least one terminal by
a core network device.
Description
BACKGROUND
(1) Field
The present invention relates generally to a method and a device
for identifying at least one terminal for which signals transferred
between the at least one terminal and a base station of a wireless
cellular telecommunication network have to be relayed by a
relay.
(2) Description of the Related Art
Future wireless cellular telecommunication network will use higher
frequency bands than the ones used by current wireless cellular
telecommunication networks.
New wireless cellular telecommunication networks, particularly in
urban environment, will have dead zones, wherein the signals
transferred between base stations and terminals will be highly
attenuated.
By installing relays, it is possible to reduce the dead zones.
If it is not correctly controlled, the deployment of relays in a
wireless cellular telecommunication network may degrade the overall
system performance instead of enhancing it.
Indeed, for a given cell, relays of other cells are potential new
sources of interference for the given cell. These new sources of
interferences are added to the interference generated by other base
stations.
The massive deployment of relays will put a heavy burden for
operators as they will have to connect these relays to the
telecommunication network which links the base stations.
Having relays wired-connected to the telecommunication network
increases the relay deployment cost and forbid the relays from
being easily changed of location.
BRIEF SUMMARY
The present invention aims at proposing a solution to reduce the
dead zones by the deployment of relays which don't have to be
wired-connected to telecommunication networks and for which the
relaying operation mode is controlled.
To that end, the present invention concerns a method, implemented
on a communication system, for identifying at least one terminal
for which signals transferred between the at least one terminal and
a base station of a wireless cellular telecommunication network
have to be relayed by a relay device, the base station providing a
random access channel enabling a terminal to notify to the base
station the presence of the terminal by transferring a random
access signal to the base station, the method comprising:
transferring, by the relay device, a random access signal to the
base station over the random access channel to notify the base
station of the presence of the relay device, wherein the relay
device is initially considered by the base station to be a new
terminal in an area managed by the base station after receiving the
random access signal;
informing, by the relay device, the base station, after a response
to the transferred random access signal is received, that the relay
device is a relay that is configured to relay signals between the
base station and at least one terminal, for authentication as the
relay that is configured to relay signal between the base station
and at least one terminal by a core network device;
relaying, by the relay device, signals between at least one
terminal and the base station.
The present invention also concerns a method, implemented on a
communication system, for notifying the presence of a relay device
to a base station, the relay device being able to relay signals
transferred between at least one terminal and the base station of a
wireless cellular telecommunication network, the base station
providing a random access channel enabling a terminal to notify to
the base station the presence of the terminal by transferring a
random access signal to the base station, the method
comprising:
transferring, by the relay device, a random access signal to the
base station over the random access channel to notify the base
station of the presence of the relay device, wherein the relay
device is initially considered by the base station to be a new
terminal in an area managed by the base station after receiving the
random access signal; and
informing, by the relay device, the base station, after a response
to the transferred random access signal is received, that the relay
device is a relay that is configured to relay signals between the
base station and at least one terminal, for authentication as the
relay that is configured to relay signals between the base station
and at least one terminal by a core network device.
The present invention also concerns a method, implemented on a
communication system, for notifying the presence of a relay device
to a base station, the relay device being able to relay signals
transferred between at least one terminal and the base station of a
wireless cellular telecommunication network, the base station
providing a random access channel enabling a terminal to notify to
the base station the presence of the terminal by transferring a
random access signal to the base station, the method
comprising:
receiving, by the base station, a random access signal from the
relay device over the random access channel to notify the base
station of the presence of the relay device, wherein the relay
device is initially considered by the base station to be a new
terminal in an area managed by the base station after receiving the
random access signal; and
receiving, by the base station, after a response to the transferred
random access signal is transferred, information from the relay
device notifying that the relay device is a relay that is
configured to relay signals between the base station and at least
one terminal, for authentication as the relay that is configured to
relay signals between the base station and at least one terminal by
a core network device.
The present invention also concerns a relay device of a wireless
cellular telecommunication network in which the relay device is
configured to relay signals transferred between at least one
terminal and a base station, and the base station provides a random
access channel enabling a terminal to notify to the base station
the presence of the terminal by transferring a random access signal
to the base station, the relay device comprising:
means for transferring a random access signal to the base station
over the random access channel to notify the base station of the
presence of the relay device, wherein the relay device is initially
considered by the base station to be a new terminal in an area
managed by the base station after receiving the random access
signal,
means for informing the base station, after a response to the
transferred random access signal is received, that the relay device
is the relay that is configured to relay signals between the base
station and at least one terminal, for authentication as the relay
that is configured to relay signals between the base station and at
least one terminal by a core network device; and
means for relaying signals between at least terminal and the base
station.
Thus, it is no more necessary to wire-connect the relay to the
telecommunication network of the wireless cellular
telecommunication network.
By using a signal classically used by terminals, the relay can
establish a connection with the wireless cellular telecommunication
network without needing any particular modification of the wireless
cellular telecommunication network.
Furthermore, by determining at least one terminal for which signals
have to be relayed, it is possible to adapt the operation of the
relay to the conditions of the wireless cellular telecommunication
network. As the signals relayed are controlled, less interference
on neighbouring cells is generated.
Furthermore, as the relay uses the same signaling as terminals, the
relay can move.
According to a particular feature, the relay device: receives a
message requesting the relay device to switch in an idle mode,
interrupts the relay of the signals transferred between each
identified terminal and the base station.
Thus, the operation of the relay is adapted to the conditions of
the wireless cellular telecommunication network. As the signals
relayed are controlled, less interference on neighbouring cells is
generated.
According to a particular feature, the relay device, prior to
receiving the message, transfers information representative of
measurement of signals transferred by at least one terminal to the
base station which handles the terminal.
Thus, it is possible to know which terminals may be good candidates
for the list of at least one terminal. The operation of the relay
is adapted to the conditions of the wireless cellular
telecommunication network.
According to a particular feature, information representative of
measurement of signals transferred by at least one terminal are
information identifying the resource blocks of at least one channel
between the base station and the terminal for which the relay
device measures the highest received signal power strength.
Thus, it is possible to know which resource blocks may be good
candidates for the relaying of signals. The operation of the relay
is adapted to the conditions of the wireless cellular
telecommunication network.
According to a particular feature, a management entity manages the
relay device located in the area managed by the base station.
According to a particular feature, the relay device receives a
list, identifies from the received list at least one terminal for
which signals transferred between the at least one identified
terminal and the base station have to be relayed by the relay
device, and
the management entity: receives the information identifying the
resource blocks, obtains, from the base station, at least one
identifier of the terminal to which the identified resource blocks
are allocated, determines, from the at least one obtained
identifier of terminal, the list of at least one terminal.
Thus, it is possible to know which terminals may be good
candidates. The operation of the relay is adapted to the conditions
of the wireless cellular telecommunication network.
Furthermore, as the relay does not need to identify the terminals
during measurements, the wireless cellular telecommunication does
not need to be modified a lot.
According to a particular feature, the management entity obtains,
from the base station, at least one identifier of the terminal for
which the transmission quality between the terminal and the base
station is below a given threshold and the list of at least one
terminal is further determined from the at least one obtained
identifier of terminal for which the transmission quality between
the terminal and the base station is below the given threshold.
Thus, it is possible to know which terminals may be good
candidates. The operation of the relay is adapted to the conditions
of the wireless cellular telecommunication network.
According to a particular feature, the relay device receives a
list, identifies from the received list at least one terminal for
which signals transferred between the at least one identified
terminal and the base station have to be relayed by the relay
device, and the management entity receives information
representative of measurement of signals transferred between the
base station and the relay, and the list of at least one terminal
is further determined from information representative of
measurement of signals transferred between the base station and the
relay.
Thus, it is possible to determine if the relay is a good candidate
for relaying signals transferred between the base station and at
least one terminal. For example, if the relay is moving and the
link conditions between the relay and the base station decrease,
the relay should not relay signals and the management entity may
select another relay for relaying signals transferred between the
base station and the terminal.
According to a particular feature, the management entity transfers
a message requesting the relay device to stop to transfer signals
transferred between the at least one terminal and the base station
which handles the terminal if signals don't need to be relayed.
Thus, the operation of the relay is adapted to the conditions of
the wireless cellular telecommunication network.
According to a particular feature, the management entity transfers
a paging message to the relay device.
Thus, by using a signal classically used for terminals, the
management entity can wake up the relay and/or determine the
location of the relay without needing any particular modification
of the wireless cellular telecommunication network.
According to a particular feature, the message and/or the
information transferred between the management entity and the relay
device are transferred via a radio interface of the base
station.
Thus, by using the resource of the base station, there is no need
to modify the architecture of the wireless cellular
telecommunication network.
According to a particular feature, the base station allocates an
identifier to the relay device, the identifier being selected among
identifiers to be allocated to terminals.
Thus, as the base station does not need to be aware of the relaying
characteristic, by using classical identifier normally used for
terminal, the base station does not need to be modified and the
relay can be identified. There is no need of particular
modifications of the wireless cellular telecommunication
network.
According to a particular feature, the relay device receives a
list, identifies from the received list at least one terminal for
which signals transferred between the at least one identified
terminal and the base station have to be relayed by the relay
device, and the at least one identified terminal is identified in
the received list.
According to still another aspect, the present invention concerns a
non-transitory computer readable medium including computer
executable instructions or portions of code for causing a relay
device of a wireless cellular telecommunication network, in which
the relay device is configured to relay signals transferred between
at least one terminal and a base station and the base station
provides a random access channel enabling a terminal to notify to
the base station the presence of the terminal by transferring a
random access signal to the base station, to perform a method
comprising:
transferring, by the relay device, a random access signal to the
base station over the random access channel to notify the base
station of the presence of the relay device, wherein the relay
device is initially considered by the base station to be a new
terminal in an area managed by the base station after receiving the
random access signal;
informing, by the relay device, the base station, after a response
to the transferred random access signal is received, that the relay
device is a relay that is configured to relay signals between the
base station and at least one terminal, for authentication as the
relay that is configured to relay signals between the base station
and at least one terminal by a core network device; and
relaying, by the relay device, signals between at least one
terminal and the base station.
Since the features and advantages relating to the computer program
are the same as those set out above related to the method and
device according to the invention, they will not be repeated
here.
BRIEF DESCRIPTION OF THE DRAWINGS
The characteristics of the invention will emerge more clearly from
a reading of the following description of an example embodiment,
the said description being produced with reference to the
accompanying drawings, among which:
FIG. 1 represents the architecture of a wireless cellular
telecommunication network in which the present invention is
implemented;
FIG. 2 is a diagram representing the architecture of a relay in
which the present invention is implemented;
FIG. 3 is a diagram representing the architecture of a management
entity in which the present invention is implemented;
FIG. 4 is a diagram representing the architecture of a base station
in which the present invention is implemented;
FIGS. 5a and 5b disclose an example of an algorithm executed by the
relay according to the present invention;
FIG. 6 discloses an example of an algorithm executed by the base
station according to the present invention;
FIGS. 7a, 7b and 7c disclose an example of an algorithm executed by
the management entity according to the present invention.
DETAILED DESCRIPTION
FIG. 1 represents the architecture of a wireless cellular
telecommunication network in which the present invention is
implemented.
In the wireless cellular telecommunication network, a base station
BS transfers signals to at least one terminal TE.
The base station BS is also named an access node or a node B or an
enhanced node B.
A base station BS handles a terminal TE when the base station BS
has the information necessary for enabling the terminal TE to
establish a communication with a remote device through the base
station BS.
An area or a cell managed by a base station BS is an area in which
the base station BS and a terminal TE in the cell can
communicate.
The base station BS transfers signals to the terminal TE through a
downlink channel and receives signals transferred by the terminal
TE through an uplink channel.
In the FIG. 1, one relay RL is shown. The relay RL may work into
three modes. A relay mode wherein the relay RL relays signals
transferred between the base station BS and at least one terminal
TE, an idle mode wherein the relay RL is in an idle mode as the
idle mode known for terminals TE of classical wireless cellular
telecommunication networks and an active mode wherein a connection
is established between the relay RL and a management entity ME but
wherein the relay doesn't not relay signals transferred between the
base station BS and at least one terminal TE. The active mode is an
intermediate mode between the relay mode and the idle mode.
The idle mode is a mode wherein no connection is established
between the relay RL and a management entity ME, wherein the relay
RL doesn't relay any signal transferred between the base station BS
and at least one terminal TE and doesn't transfer signals enabling
the determination of position of the relay to any other device of
the wireless cellular telecommunication network.
According to the invention, the position of the relay RL may vary.
For example, the relay RL may be located in a bus, a car, or a
train.
According to the invention, the relay RL transfers a random access
signal to the base station BS for obtaining a list of at least one
terminal TE.
The relay RL identifies, from the received list, at least one
terminal TE for which signals transferred between the at least one
identified terminal TE and the base station BS have to be relayed
by the relay RL.
The random access signal is as the one transferred by a terminal TE
in a random access channel in order, for the base station BS, to
detect the presence of the terminal TE.
When the relay RL acts as a relay, it receives signals transferred
by the base station BS which handles the terminal TE in the
downlink channel and transfers these signals to the terminal TE
through the downlink channel and/or receives signals transferred by
the terminal TE through the uplink channel and transfers these
signals in the uplink channel to the base station BS which handles
the terminal TE.
It has to be noted here that the relay RL may also operate into
other different modes. For example, the relay RL may operate like a
femto base station.
The base station BS is linked to a telecommunication network TN
which links each base station BS to core network devices CN which
handle the operation of the wireless cellular telecommunication
network.
The core network devices CN execute the same operation as classical
core network devices in classical wireless cellular
telecommunication networks.
In FIG. 1, one management entity ME is shown. The management entity
ME is included in at least one base station BS and manages one
relay RL or plural relays RL included into at least one cell of the
base station BS.
In a variant, the management entity ME is not included in the base
station BS and manages plural relays RL included into the cells of
plural base stations BS linked to the management entity ME through
the telecommunication network TN.
Some of the relays RL may work in the relay mode, others in the
idle or active mode.
The management entity ME may be also named a relay controller.
In the FIG. 1, only one base station BS, one management entity ME
and one relay RL are shown for the sake of clarity but in practice
the wireless cellular telecommunication network comprises a large
number of base stations BS, management entities ME and relays
RL.
The terminal TE is, for example, a mobile phone, a personal digital
assistant, a personal computer.
In FIG. 1, only one terminal TE is shown for the sake of clarity
but in practice the wireless cellular telecommunication network
comprises a large number of terminals TE.
FIG. 2 is a diagram representing the architecture of a relay in
which the present invention is implemented.
The relay RL has, for example, an architecture based on components
connected together by a bus 201 and a processor 200 controlled by
the program as disclosed in the FIG. 5.
The bus 201 links the processor 200 to a read only memory ROM 202,
a random access memory RAM 203 and a wireless interface 205.
The memory 203 contains registers intended to receive variables and
the instructions of the program as disclosed in the FIG. 5.
The processor 200 controls the operation of the wireless interface
205.
The read only memory 202 contains instructions of the program as
disclosed in the FIG. 5, which are transferred, when the relay RL
is powered on to the random access memory 203.
The wireless interface 205 enables the relay RL to transfer and/or
receive signals or messages to the base station BS and to the at
least one terminal TE included in the list of at least one terminal
TE.
The wireless interface 205 may comprise a downlink reception module
210 which receives signals transferred by at least one base station
BS, may comprise a downlink transmission module 211 which transfers
signals to at least one terminal TE, may comprise an uplink
reception module 212 which receives signals transferred by at least
one terminal TE and may comprise an uplink transmission module 213
which transfer signals to at least one base station BS.
FIG. 3 is a diagram representing the architecture of a management
entity in which the present invention is implemented.
The management entity ME has, for example, an architecture based on
components connected together by a bus 301 and a processor 300
controlled by the program as disclosed in the FIG. 7.
The bus 301 links the processor 300 to a read only memory ROM 302,
a random access memory RAM 303 and a network interface 306.
The memory 303 contains registers intended to receive variables and
the instructions of the program related to the algorithm as
disclosed in the FIG. 7.
The processor 300 controls the operation of the network interface
306.
The read only memory 302 contains instructions of the programs
related to the algorithm as disclosed in the FIG. 7, which are
transferred, when the management entity ME is powered on to the
random access memory 303.
The management entity ME may be connected to the telecommunication
network TN through the network interface 306. For example, the
network interface 306 is a DSL (Digital Subscriber Line) modem, or
an ISDN (Integrated Services Digital Network) interface, etc.
Through such interface, the management entity ME may transfer
messages to at least one relay RL and/or to at least one base
station BS and/or receive message from at least one relay RL and/or
from at least one base station BS.
It has to be noted here that, when the management entity ME is
included in a base station BS, the processor 300, the memory 302,
the random access memory RAM 303 and the network interface 306 may
be the ones of the base station BS.
FIG. 4 is a diagram representing the architecture of a base station
in which the present invention is implemented.
The base station BS has, for example, an architecture based on
components connected together by a bus 401 and a processor 400
controlled by the program as disclosed in the FIG. 6.
The bus 401 links the processor 400 to a read only memory ROM 402,
a random access memory RAM 403, a wireless interface 405 and a
network interface 406.
The memory 403 contains registers intended to receive variables and
the instructions of the program related to the algorithm as
disclosed in the FIG. 6.
The processor 400 controls the operation of the network interface
406 and of the wireless interface 405.
The read only memory 402 contains instructions of the programs
related to the algorithm as disclosed in the FIG. 6, which are
transferred, when the base station BS is powered on to the random
access memory 403.
The base station BS is connected to the telecommunication network
TN through the network interface 406. For example, the network
interface 406 is a DSL (Digital Subscriber Line) modem, or an ISDN
(Integrated Services Digital Network) interface, etc. Through such
interface, the base station BS may transfer messages to at least
one management entity ME or to core network devices CN which manage
the wireless cellular telecommunication network.
The wireless interface 405 comprises at least a downlink
transmission module not shown in the FIG. 1 which transfers signals
to at least one terminal TE relayed or not by the relay RL and an
uplink reception module not shown in the FIG. 1 which receives
signals transferred by at least one terminal TE, relayed or not by
the relay RL.
FIGS. 5a and 5b disclose an example of an algorithm executed by the
relay according to the present invention.
More precisely, the present algorithm is executed by the processor
200 of the relay RL.
At step S500 of the FIG. 5a, the processor 200 commands the
wireless interface 205 to transfer a random access signal RACH
through a random access channel of a base station BS which manages
the cell in which the relay RL is located.
The random access signal is transferred for example when the relay
RL is powered on or when the relay RL enters in an area unknown by
the relay RL.
At next step S501, the processor 200 receives, through the wireless
interface 205, a temporary identifier UEID allocated by the base
station BS to the relay RL. The temporary identifier UEID uniquely
identifies the relay RL in the cell managed by the base station BS.
The identifier UEID, which uniquely identifies the relay RL, is
selected among plural identifiers which may uniquely identify a
terminal TE located in the cell managed by the base station BS.
It has to be noted here that, as the relay RL uses the same random
access signal RACH used by a terminal TE for notifying its presence
in the cell of the base station BS, the relay RS is considered to
be a new terminal TE in the cell of the base station BS.
At next step S502, the processor 200 enters into an
identification/authentication procedure with at least one core
network device CN of the wireless cellular telecommunication
network.
At that step, the processor 200 informs the core network device CN
or the base station BS that the relay RL is not a terminal TE but a
relay which may, in a relay operation mode, relay signals
transferred between the base station BS and at least one terminal
TE.
At the same time, the relay RL is authenticated in a similar way as
a classical wireless cellular telecommunication network
authenticates a terminal TE.
At next step S503, the processor 200 receives through the wireless
interface 205, a unique identifier TEID from a core network device
CN of the wireless cellular telecommunication network.
The unique identifier TEID uniquely identifies the relay RL in the
wireless cellular telecommunication network or uniquely identifies
the relay RL in a group of cells of the wireless cellular
telecommunication network. The identifier TEID, which uniquely
identifies the relay RL, is selected among plural identifiers which
may uniquely identify a terminal TE in the wireless cellular
telecommunication network or in a group of cells of the wireless
cellular telecommunication network.
It has to be noted here that, the order of the reception of the
UEID and TEID may be different as the one disclosed in the present
algorithm.
At next step S504, a connection is established between the relay RL
and the management entity ME.
When the management entity ME is included in the base station BS,
the connection between the relay RL and the management entity ME is
established between the relay RL and the base station BS through
their respective wireless interfaces 205 and 405.
When the management entity ME is not included in the base station
BS, the connection between the relay RL and the management entity
ME is decomposed into a first sub-connection established between
the relay RL and the base station BS through their respective
wireless interfaces 205 and 405 and into a second sub-connection
between the base station BS and the management entity ME through
their respective network interfaces 406 and 306.
At the same step, the management entity ME memorizes the couple of
UEID and TEID allocated to the relay RL. The management entity ME
may initiate the connection using the couple of unique identifiers
or the relay RL may initiate the connection from indication
provided by the core network device CN of the wireless cellular
telecommunication network.
At next step S505, the processor 200 detects the reception through
the wireless interface 205 of a request for obtaining the features
of the relay RL.
The features of the relay RL are for example, the position of the
relay as the one provided by a Global Navigation Satellite System,
if the relay is able to schedule or not the retransmission of the
received signals and/or if the relay is able to decode and
retransmit the received signals and/or if the relay is able to
determine to which terminal TE signals are transferred or from
which terminal TE signal are transmitted and/or if the relay RL is
able to retransmit signals onto different frequency resources or is
able to retransmit signals using different modulation and/or coding
scheme than the one used for the transmission of the signals
received by the relay RL and/or which protocol is supported by the
relay RL.
At next step S506, the processor 200 commands the transfer through
the wireless interface 205 of the features of the relay RL.
It has to be noted here that in a variant, the features of the
relay RL are transferred during the identification step S502. In
that variant, the processor 200 moves from step S504 to step
S507.
In another variant, once the connection is established at step
S504, the processor 200 moves from step S504 to S506 and commands
the transfer through the wireless interface 205 of the features of
the relay RL.
At next step S507, the processor 200 checks if a sounding request
is received through the wireless interface 205. The sounding
request is transferred by the management entity ME.
If a sounding request is received, the processor 200 moves to step
S508. Otherwise, the processor 200 moves to step S520.
At next step S508, the processor 200 commands the wireless
interface 205 to sound received signals i.e. to monitor the signals
received in each radio Physical Resource Block PRB.
A Physical Resource Block is a part of the downlink channel and/or
of the uplink channel. A Physical Resource Block is composed of at
least one time and/or frequency resource of the downlink channel
and/or of the uplink channel.
For example, the power strengths of the signals transmitted by the
terminals TE and received by the relay RL in each radio Physical
Resource Block are monitored and/or the power strengths of the
signals transmitted by the base station BS and received at the
relay in each radio Physical Resource Block are monitored.
At next step S509, the processor 200 commands the wireless
interface 205 to transfer to the management entity ME, information
identifying the M Physical Resource Blocks PRB on which the
received signals power strength are the M highest, M being an
integer at least equal to one.
In a variant, the processor 200 commands the wireless interface 205
to determine the terminals TE which transfer the signals having the
M highest received signals power strength and to transfer the M
identifiers of the determined terminals TE.
After that, the processor 200 returns to step S507.
At step S520, the processor 200 checks if a handover command
message is received through the wireless interface 205.
If a handover request message is received, the processor 200 moves
to step S521. Otherwise, the processor 200 moves to step S550 of
the FIG. 5b.
At step S521, the relay RL executes a handover procedure as a
classical terminal TE executes a handover in a classical wireless
cellular telecommunication network.
After that, the processor 200 returns to step S500.
At step S550, the processor 200 checks if an idle command is
received through the wireless interface 205 from the management
entity ME.
If an idle command is received, the processor 200 moves to step
S551. Otherwise, the processor 200 moves to step S560.
At step S551, the processor 200 commands the wireless interface 205
to switch to the idle mode. The wireless interface 205 stops to
relay signals and interrupts the transmission of some signals like
the ones used for localizing a terminal TE.
At step S552, the processor 200 waits the reception, through the
wireless interface 205, of a paging message issued by the
management entity ME. A paging message is classically used by the
core network devices CN in order to inform a terminal TE that there
is an incoming call for it.
When a paging message is received, the processor 200 moves to step
S553.
At step S553, the processor 200 commands the transfer of the random
access signal RACH through the random access channel of the base
station BS which manages the area in which the relay RL is
located.
The random access signal is transferred in response to the received
paging message.
At next step S554, the processor 200 receives through the wireless
interface 206, another temporary identifier UEID allocated to the
relay RL by the base station BS. The temporary identifier UEID
uniquely identifies the relay RL in the cell managed by the base
station BS. The temporary identifier UEID which uniquely identifies
the relay RL is selected among plural temporary identifiers which
may uniquely identify a terminal TE located in the cell managed by
the base station BS.
At next step S555, the processor 200 enters into an
identification/authentication procedure with the management device
ME as it has been disclosed at step S502 of the FIG. 5a.
After that, the processor 200 returns to step S507 of the FIG.
5a.
At step S560, the processor 200 checks if a list of at least one
terminal TE is received through the wireless interface 205.
If a list of at least one terminal TE is received, the processor
200 moves to step S561. If no list of at least one terminal TE is
received, the processor 200 returns to step S507 of the FIG.
5a.
At step S561, the processor 200 identifies, from the received list
of at least one terminal TE, at least one terminal TE for which
signals transferred between the at least one identified terminal TE
and the base station BS have to be relayed by the relay RL.
For example, the list of at least one terminal TE comprises the
identifier of each terminal TE for which signals transferred
between the base station BS and the terminal TE have to be
relayed.
The processor 200 identifies the at least one terminal TE for which
signals transferred between the at least one identified terminal TE
and the base station BS have to be relayed by the relay RL by
reading the identifiers comprised in the list of at least one
identifier.
For example, the list of at least one terminal TE comprises the
identifier of each new terminal TE for which signals transferred
between the base station BS and the terminal TE have to be
relayed.
The processor 200 identifies the at least one terminal TE for which
signals transferred between the at least one identified terminal TE
and the base station BS have to be relayed by the relay RL by
adding each identifier comprised in the received list of at least
one identifier to a memorized list of terminal TE for which signals
transferred between the at least one identified terminal TE and the
base station BS had to be relayed by the relay RL.
For example, the list of at least one terminal TE comprises the
identifier of each terminal TE for which the relaying of signals
transferred between the base station BS and the terminal TE has to
be interrupted.
The processor 200 identifies the at least one terminal TE for which
signals transferred between the at least one identified terminal TE
and the base station BS have to be relayed by the relay RL by
removing each identifier comprised in the received list of at least
one identifier to a memorized list of terminal TE for which signals
transferred between the at least one identified terminal TE and the
base station BS had to be relayed by the relay RL.
At next step S562, the processor 200 commands the wireless
interface 205 to monitor, decode and code the signals transferred
by the base station BS to each identified terminal TE and/or to
monitor, decode and code the signals transferred to the base
station BS by each identified terminal TE.
At next step S563, the processor 200 commands the wireless
interface 205 to retransmit the monitored decoded and coded signals
to the terminal TE and/or to the base station BS.
For example, in a first step, the relay RL receives the signal
to/from a terminal TE on a frequency resource allocated to the
terminal TE by the Base Station BS and in a second step, the relay
RL retransmits on the same frequency resource the received signal
without modification of the signal, while the base station BS does
not transmit on the frequency resource.
For example, in a first step, the relay RL receives the signal
to/from a terminal TE on a frequency resource allocated to the
terminal TE by the Base Station BS and in a second step, the relay
RL retransmits on the same frequency resource the received signal
without modification, while the base station BS transmits another
signal to the same terminal TE on the frequency resource.
For example, in a first step, the relay RL receives the signal
to/from a terminal TE on a frequency resource allocated to the
terminal TE by the Base Station BS and in a second step, the relay
RL retransmits on the same frequency resource the received signal
without modification, while the base station BS transmits a signal
to another terminal TE on the frequency resource.
For example, in a second step, the relay RL receives and decodes
the signal of a terminal TE on a frequency resource allocated to
the terminal TE by the Base Station BS and in a second step, the
relay RL re-encodes and transmits on the same frequency resource
the received signal without modification, while the base station BS
does not transmit on the frequency resource.
After that, the processor 200 returns to step S507 of the FIG.
5a.
FIG. 6 discloses an example of an algorithm executed by the base
station according to the present invention.
More precisely, the present algorithm is executed by the processor
400 of the base station BS.
At step S600, the processor 400 checks if a random access signal
RACH is received through the random access channel of the base
station BS.
The random access signal RACH is classically transferred by a new
terminal TE located in the cell managed by the base station BS or
transferred in response to a paging message or when a terminal TE
is powered on.
If the random access signal is received, the processor 400 moves to
step S601. Otherwise, the processor 400 moves to step S604.
At step S601, the processor 400 commands the transfer through the
wireless interface 206, in response to the received random access
signal RACH, of a temporary identifier UEID allocated by the base
station BS to the supposed terminal TE which sent the RACH signal.
The temporary identifier UEID uniquely identifies the supposed
terminal TE in the cell managed by the base station BS.
At next step S602, an identification/authentication procedure is
established between the supposed terminal TE and at least one core
network device CN of the wireless cellular telecommunication
network.
At that step, the base station BS becomes aware that the supposed
terminal TE is the relay RL.
The base station BS or the core network device CN notifies the
management entity ME that a new relay RL is located in the cell
managed by the base station BS and transfers to the management
entity ME, the UEID and TEID allocated to the terminal TE.
It has to be noted here that in a variant, the relay RL transfers
the allocated UEID and TEID to the management entity ME.
At the same time, the relay RL is authenticated in a similar way as
a classical wireless cellular telecommunication network
authenticates a terminal TE.
At next step S603, a connection is established between the relay RL
and the management entity ME.
When the management entity ME is included in the base station BS,
the connection between the relay RL and the management entity ME is
established between the relay RL and the base station BS through
their respective wireless interfaces 205 and 405.
When the management entity ME is included in the base station BS,
the connection between the relay RL and the management entity ME is
decomposed into a first sub-connection established between the
relay RL and the base station BS through their respective wireless
interfaces 205 and 405 and into a second sub-connection between the
base station BS and the management entity ME through their
respective network interfaces 406 and 306.
The management entity ME may initiate the connection using the
couple of unique identifiers or the relay RL may initiate the
connection from indication provided by the core network devices
CN.
After that, the processor 400 returns to step S600.
At step S604, the processor 400 checks if a paging message is
received from the management entity ME.
If a paging message is received, the processor 400 moves to step
S605. Otherwise, the processor 400 moves to step S606.
At step S605, the processor 400 commands the transfer of the paging
message through the wireless interface 405.
After that, the processor 400 returns to step S600.
At step S606, the processor 400 checks if a scheduler information
request is received from the management entity ME through the
network interface 406.
If a scheduler information request is received, the processor 400
moves to step S607. Otherwise, the processor 400 moves to step
S610.
At step S607, the processor 400 obtains the identifiers of the
terminals TE to which, the physical resource blocks PRB transmitted
during the scheduler information request, have been allocated by
the base station BS.
In a variant, the processor 400 obtains identifiers of the
terminals TE to which the base station BS has allocated at least
one physical resource blocks PRB.
At next step S608, the processor 400 commands the transfer, to the
management entity ME, of the identifiers of the terminals TE to
which, the physical resource blocks transmitted during the
scheduler information request, have been allocated.
In a variant, the processor 400 commands the transfer, to the
management entity ME, of the identifiers of the terminals TE to
which, at least one physical resource block has been allocated by
the base station in combination with information identifying the
physical resource blocks.
At next step S609, the processor 400 commands the transfer of the
identifiers of the terminals TE handled by the base station BS for
which the transmission quality between the terminal TE and the base
station BS is below a given threshold.
As example, the transferred identifiers are the identifiers of the
terminals TE which are identified as having a low throughput in
comparison with others.
These terminals TE are identified, for example, by monitoring the
number of retransmission of packets which have been executed over a
given period of time.
After that, the processor 400 returns to step S600.
At step S610, the processor 400 checks if a handover is needed.
If a handover is needed, the processor 400 moves to step S611.
Otherwise, the processor 400 returns to step S600.
At step S611, the processor 400 executes a handover procedure as
for a classical terminal TE in a classical wireless cellular
telecommunication network.
After that, the processor 400 returns to step S600.
FIGS. 7a, 7b and 7c disclose an example of an algorithm executed by
the management entity according to the present invention.
More precisely, the present algorithm is executed by the processor
300 of the management entity ME.
When the management entity ME manages relays RL included into at
least one cell of one base station BS, the present algorithm is
executed in parallel for each relay RL comprised in the cell of the
base station BS.
When the management entity ME manages relays RL included into cells
of plural base stations BS, the present algorithm is executed in
parallel for each relay RL comprised in the cell of each base
station BS.
At step S700, the processor 300 detects the reception of a message
comprising the identifiers UEID and TEID allocated to the relay RL.
The message is transferred by the base station BS or by the core
network CN.
It has to be noted here that in a variant, the relay RL transfers
the allocated UEID and TEID to the management entity ME.
At next step S701, a connection is established between the relay RL
and the management entity ME.
When the management entity ME is included in the base station BS,
the connection between the relay RL and the management entity ME is
established between the relay RL and the base station BS through
their respective wireless interfaces 205 and 405.
When the management entity ME is included in the base station BS,
the connection between the relay RL and the management entity ME is
decomposed into a first sub-connection established between the
relay RL and the base station BS through their respective wireless
interfaces 205 and 405 and into a second sub-connection between the
base station BS and the management entity ME through their
respective network interfaces 406 and 306.
The management entity ME may initiate the connection using the
couple of unique identifiers or the relay RL may initiate the
connection from indication provided by the core network CN.
At step S702, the processor 300 commands the transfer of a request
for obtaining the features of the relay RL.
The features of the relay RL are for example, the position of the
relay as the one provided by a Global Navigation Satellite System,
if the relay is able to schedule or not the retransmission of the
received signals and/or if the relay is able to decode and
retransmit the received signals and/or if the relay is able to
determine to which terminal TE signals are transferred or from
which terminal TE signals are transmitted and/or if the relay RL is
able to retransmit signals onto different frequency resources or is
able to retransmit signals using different modulation and/or coding
scheme than the one used for the transmission of the signals
received by the relay RL and/or which protocol is supported by the
relay RL.
At next step S703, the processor 300 receives the features of the
relay RL.
It has to be noted here that in a variant, the features of the
relay RL are received during the identification step S701 of the
FIG. 7a. In that variant, the processor 300 starts the algorithm of
the FIG. 7b at S752.
At next step S704, the processor 300 checks if the relay RL is in
the idle mode.
If the relay is in the idle mode, the processor 300 moves to step
S705. Otherwise, the processor 300 moves to step S715.
At step S705, the processor 300 checks if the relay RL needs to be
activated.
The relay RL may need to be activated when no other relay RL or few
other relays relay signals transferred between at least one
terminal TE and the base station BS.
The relay RL may need to be activated if the relay RL has better
features than the ones of another relay RL which is currently
relaying signals.
If the relay RL needs to be activated, the processor 300 moves to
step S706.
Otherwise, the processor 300 returns to step S704.
At step S706, the processor 300 commands the transfer of a paging
message to the relay RL. The paging message is transferred to the
base station BS which handles the cell in which the relay RL is
supposed to be located or to plural base stations BS surrounding
the base station BS which handles the cell in which the relay RL is
supposed to be located. The base station BS or base stations BS
transfer the paging message in their cell or cells.
At next step S707, the processor 300 checks if a response message
is received in response to the paging message.
The response message is transferred by the base station BS which
manages the cell in which the relay RL is located. The response
message is transferred by the base station BS once the base station
BS receives a random access message RACH from the relay RL.
If a response message is received, the processor 300 moves to step
S709. Otherwise, the processor 300 moves to step S708.
At step S708, the processor 300 commands the deletion of the
context of the relay RL.
The context of the relay RL comprises the temporary identifiers
allocated to the relay RL, the list of at least one terminal TE
determined for the relay RL and may comprise the features of the
relay RL.
More generally, the context of the relay RL may comprise all the
information related to the relay RL memorized in the management
entity ME.
After that, the processor 300 interrupts the present algorithm for
the relay RL.
At step S709, the processor 300 detects the reception of a message
comprising the identifier TEID allocated to the relay RL and a new
UEID allocated to the relay RL. The message is transferred by the
base station BS or by the core network devices CN.
It has to be noted here that in a variant, the relay RL transfers
the allocated UEID and TEID to the management entity ME.
At next step S710, a connection is established between the relay RL
and the management entity ME as it has been disclosed as step
S701.
After that, the processor 300 returns to step S704.
At step S715, the processor 300 checks if a handover is needed for
the relay RL.
If a handover is needed, the processor 300 moves to step S720.
Otherwise, the processor 300 moves to step S730.
At step S720, the processor 300 checks if the relay is going out
from the zone handled by the management entity ME.
When the management entity ME is included in a base station BS, the
zone handled by the management entity ME is the cell or cells
managed by the base station BS.
When the management entity ME manages relays RL included into cells
of plural base stations BS, the zone handled by the management
entity ME is the cell or cells managed by each base station BS.
If the relay RL is going out from the zone handled by the
management entity ME, the processor 300 moves to step S721.
Otherwise, the processor 300 moves to step S722.
At step S721, the processor 300 commands the deletion of the
context of the relay RL.
In a variant, the processor 300 commands the transfer of the
feature of the relay to the management entity ME which handles the
area in which the relay RL is now located.
After that, the processor 300 interrupts the present algorithm for
the relay RL.
At step S722, the processor commands the deletion of the list of at
least one terminal determined for the relay RL.
At next step S723, the processor 300 memorizes the context of the
relay RL in combination with the temporary identifier TEID.
After that, the processor 300 returns to step S700.
At step S730, the processor 300 checks if it is time to form a new
list.
For example, a new list is formed periodically or when a terminal
TE comprised in the list is no more in the cell managed by the base
station BS.
If it is time to form a new list, the processor 300 moves to step
S731, otherwise, the processor 300 returns to step S704.
At next step S731, the processor 300 forms a list. The step S731
will be described more precisely in reference to the FIG. 7c.
At next step S732, the processor 300 determines if the relay RL has
to relay signals transferred between at least one terminal TE and
the base station BS.
If the list comprises the identifier of each terminal TE for which
signals transferred between the base station BS and the terminal TE
have to be relayed, the processor 200 checks if the list is empty.
If the list is not empty, the relay RL has to relay signals
transferred between at least one terminal TE and the base station
BS.
If the list of at least one terminal TE comprises the identifier of
each terminal TE for which the relaying of signals transferred
between the base station BS and the terminal TE has to be
interrupted, the processor 300 removes each identifier comprised in
the list to a memorized list of terminal TE for which signals
transferred between the at least one identified terminal TE and the
base station BS had to be relayed by the relay RL and checks if the
modified memorized list is empty. If the modified memorized list is
not empty, the relay RL has to relay signals transferred between at
least one terminal TE and the base station BS.
If the relay RL has to relay signals transferred between at least
one terminal TE and the base station BS, the processor 300 moves to
step S740. Otherwise, the processor 300 moves to step S733.
It has to be noted here that in a variant, the list of at least one
terminal is determined according to the quality of the link between
the relay RL and the base station BS.
If the quality of the link between the relay RL and the base
station BS is below a given threshold, the processor 300 may decide
that the relay RL has to interrupt the relay of signals. The formed
list comprises then the identifiers of terminals which reflect that
the relay RL has to stop to relay signals.
At step S733, the processor 300 checks if the relay RL has to be
switched in the idle mode.
For example, a relay has to be switched in the idle mode when
plural consecutive lists determined at step S731 reflect that the
relay RL has to stop to relay signals.
If the relay RL has to be switched in the idle mode, the processor
300 moves to step S734. Otherwise, the processor 300 returns to
step S704.
In the case the processor 300 returns to step S704, the relay RL is
in the active mode. In the active mode, the connection is
maintained between the relay RL and the management entity ME but
the relay RL doesn't relay signals transferred between the base
station BS and at least one terminal TE.
At step S734, the processor 300 commands the transfer of an idle
command to the relay RL.
In the idle mode, the relay RL stops to relay signals and
interrupts the transmission of some signals like the one used for
localizing a terminal TE.
At next step S735, the processor 300 memorizes the identifier TEID,
the context of the relay RL in combination with information
indicating that the device to which the TEID is allocated is a
relay RL in idle mode.
At the same step, the connection between the relay RL and the
management entity ME is released.
After that, the processor 300 returns to step S704.
At next step S740, the processor 300 checks if the relay RL is
already in the relay mode.
If the relay RL is already in the relay mode, the processor 300
moves to step S742. Otherwise, the processor 300 moves to step
S741.
At step S741, the processor 300 commands the transfer of relay
command to the relay RL through the connection.
At step S742, the processor 300 commands the transfer to the relay
RL of the list.
At next step S743, the processor 300 memorizes the couple of
identifiers UEID and TEID in combination with information
indicating that the device to which the TEID is allocated is a
relay RL in relay mode.
After that, the processor 300 returns to step S704.
At step S750 of the FIG. 7c, the processor 300 commands the
transfer of a sounding request to the relay RL.
At next step S751, the processor 300 detects the reception of
information identifying the M Physical Resource Blocks PRB on which
the received signals power strength measured by the relay RL are
the M highest.
In a variant, the processor 300 detects the reception of M
identifiers of terminals TE for which the received signals power
strength measured by the relay RL are the M highest. In such
variant, the processor 300 moves from step S751 to S754.
At next step S752, the processor 300 commands the transfer to the
base station BS of a scheduler information request.
The scheduler information request may be a request for obtaining
the identifiers of the terminals TE to which the physical resource
blocks identified in the information received at step S751 are
allocated.
The scheduler information request may be a request for obtaining
the identifiers of the terminals TE to which physical resource
blocks have been allocated by the base station BS.
The scheduler information request may be a request for obtaining
the identifiers of the terminals TE to which a part of physical
resource blocks identified in the information received at step S751
are allocated.
At next step S753, the processor 300 obtains the identifiers of the
terminals TE to which the physical resource blocks identified in
the information received at step S753 are allocated.
The processor 300 obtains the identifiers from at least a message
transferred by the base station BS in response to the scheduler
information request.
At next step S754, the processor 300 obtains the identifiers of the
terminals TE handled by the base station BS which are identified as
having a low throughput in comparison with others.
The processor 300 obtains the identifiers of the terminals TE
handled by the base station BS which are identified as having a low
throughput from at least a message transferred by the base station
BS.
At next step S755, the processor 300 determines the list.
For example, the list is determined by selecting the identifiers of
terminals TE which are identifiers obtained at step S753 or which
are identifiers received at step S753 and S754 and/or the
identifiers of the terminals TE which have a position close to the
position of the relay RL.
In another example, the list is determined by selecting the
identifiers of terminals TE which are identifiers received at step
S753 and which were not comprised in a previous list or which are
identifiers received at step S753 and S754 and which were not
comprised in a memorized list and/or the identifiers of the
terminals TE which have a position close to the position of the
relay RL and which were not memorized in a previous list.
In another example, the list is determined by selecting the
identifiers of terminals TE which were comprised in a previous list
and which are not identified at step S753 or the identifiers of
terminals TE which were comprised in a memorized list and which are
no more identified at step S753 and S754 and/or the identifiers of
the terminals TE which have a position which becomes far from the
position of the relay RL.
Naturally, many modifications can be made to the embodiments of the
invention described above without departing from the scope of the
present invention.
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